Evacuated Tube Collector
There are mainly two types of evacuated tube solar collectors.
- All Glass vacuum tube collector
- Heat pipe type vacuum collector.
All glass vacuum tube collectors look like long thermos bottle liners; all glass vacuum tubes comprise glass tubes (outer tubes), vacuum interlayer and inner glass tube.
Heat Collection theory:
Solar Energy radiation per meters outer glass tubes to heat water in the vacuum tubes. Since cold water has bigger specific gravity and hot water has smaller specific gravity, cold water flow downwards and hot water would flow upwards in the vacuum tubes, gradually elevating water temperatures in the water tank.
The black part on the outer walls of inner tubes is selective absorption coating, also known as films, which serve as medium for light heat conversion in vacuum tubes. Sun’s rays irradiate upon the films via outer glass tubes. The films absorb the visible light and near infrared rays of sun’s rays to amass energy, translate light energy into heat energy, thus keep elevating water temperatures in the inner tubes. The selective absorption coating, made of AI-N/AI, is currently the most widely used, capable of absorbing 93% solar energy and reflecting 6%.
A vacuum interlayer is put between the outer tube and the inner tube, for the sake of reducing heat loss, preserving heat, and thus promoting thermal collection efficiency. The structures of all-glass vacuum tubes are fairly simple and production technologies are fairly mature, making it easy for plants to start the business.
Streamline outer design elegance and luxurious. Import 55MM thick polyurethane foam insulation, heat preservation over 72 hours Advance argon are welding technology Ensure non-leakage Scientific rated aperture area and tank volume, ensure perfect performance both in the South and in the North. Semi-conductor heating booster, fast heating, 10 year’s using life.